Prosthetic heart valve with reduced stitching

ABSTRACT

An implantable prosthetic valve that is radially collapsible to a collapsed configuration and radially expandable to an expanded configuration includes an annular frame including a plurality of angled strut members, and a skirt member secured to the frame. The skirt member includes a plurality of extension portions wrapped around at least one strut member adjacent the extension portions. The prosthetic valve further includes a cord member threaded through at least a portion of the plurality of extension portions to secure the skirt member to the at least one strut member.

CROSS REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. patent application Ser. No.15/709,355, filed Sep. 19, 2017, which claims the benefit of U.S.Provisional Application No. 62/398,439, filed Sep. 22, 2016. Thedisclosures of U.S. patent application Ser. No. 15/709,355 and U.S.Provisional Application No. 62/398,439 are incorporated herein byreference in their entirety.

FIELD

The present application concerns embodiments of a leaflet skirt memberand methods of attaching the skirt member to the leaflets and frame of atranscatheter heart valve.

BACKGROUND

In a typical transcatheter heart valve, the leaflets of the valve arelined with a reinforcing strip and sutured to the strut members of theframe, or sutured directly to the strut members of the frame. Thisprocess is difficult and time-consuming, and results in increased laborand cost to manufacture a valve. Accordingly, improvements to devicesand methods for securing a leaflet or leaflet assembly to a frame aredesirable.

SUMMARY

Certain embodiments of the disclosure concern implantable prostheticheart valves with leaflet-skirt assemblies. In a representativeembodiment, an implantable prosthetic valve that is radially collapsibleto a collapsed configuration and radially expandable to an expandedconfiguration comprises an annular frame including a plurality of angledstrut members, and a skirt member secured to the frame. The skirt memberincludes a plurality of extension portions wrapped around at least onestrut member adjacent the extension portions. The prosthetic valvefurther comprises a cord member threaded through at least a portion ofthe plurality of extension portions to secure the skirt member to the atleast one strut member.

In another representative embodiment, a method comprises situating askirt member adjacent a strut member of a frame of a prosthetic valve,the skirt member including a plurality of extension portions, andwrapping at least a portion of the plurality of extension portionsaround the strut member. The method further comprises threading a cordmember through the extension portions wrapped around the strut member tosecure the skirt member to the frame.

In another representative embodiment, an implantable prosthetic valvethat is radially collapsible to a collapsed configuration and radiallyexpandable to an expanded configuration comprises an annular frameincluding a plurality of angled strut members and a leaflet-skirtassembly situated within and secured to the frame. The leaflet-skirtassembly comprises a valve leaflet and a skirt member secured to an edgeportion of the valve leaflet. The skirt member has first and secondlongitudinal edge portions, and a plurality of extension portions on atleast one of the longitudinal edge portions. The extension portionsdefine tubular portions. The extension portions of the skirt member arewrapped around the strut members to secure the leaflet-skirt assembly tothe frame.

In another representative embodiment, a method comprises securing askirt member to an edge of a valve leaflet to form a leaflet-skirtassembly. The skirt member includes first and second longitudinal edgeportions and a plurality of extension portions along at least one of thelongitudinal edge portions. The extension portions define tubularportions. The method further comprises situating the leaflet-skirtassembly in a frame, and wrapping the extension portions of the skirtmember around strut members of the frame to secure the leaflet-skirtassembly to the frame.

The foregoing and other objects, features, and advantages of thedisclosed technology will become more apparent from the followingdetailed description, which proceeds with reference to the accompanyingfigures.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a representative embodiment of a framefor a prosthetic heart valve including a leaflet-skirt assembly securedthereto.

FIGS. 2-4 are plan views illustrating various embodiments of leafletskirt members.

FIG. 5 is a perspective view of a representative embodiment of a fabricmember including longitudinal tubes from which the skirt members ofFIGS. 2-4 can be made.

FIG. 6 is a side elevational view of a leaflet-skirt assembly.

FIG. 7 is a side elevational view of another embodiment of aleaflet-skirt assembly.

FIG. 8 is a perspective view of a portion of a leaflet-skirt assemblysituated in a frame illustrating extension portions of a skirt memberwrapped around strut members of the frame.

FIG. 9 is a cross-sectional view of the leaflet-skirt assembly and theframe illustrated in FIG. 8.

FIG. 10 is a perspective view of the assembly of FIG. 8 illustrating acord threaded through the tubular portions of the skirt member.

FIG. 11 is a side elevational view of a representative embodiment of aprosthetic valve including an outer skirt secured to a frame with a cordthat also secures a leaflet-skirt assembly to the frame.

FIG. 12 is a process flow diagram illustrating a representative methodof making a leaflet-skirt assembly and situating the assembly in aframe.

FIG. 13 is a cross-sectional view of an alternative embodiment of aleaflet-skirt assembly including two skirt members.

FIG. 14 is a cross-sectional view of an alternative embodiment of aleaflet-skirt assembly including a skirt member secured on one side of aleaflet.

FIG. 15 is a cross-sectional view of the leaflet-skirt assembly and theframe of FIG. 10 illustrating tubular portions of the extension portionsextending through slits in an outer skirt such that the outer skirt issecured to the frame by the cord threaded through the tubular portions.

FIG. 16 is a perspective detail view of a portion of a skirt memberincluding suture threads extending between openings in the skirt memberto form loop portions.

FIG. 17 is a perspective detail view illustrating the skirt member ofFIG. 16 secured to a strut member of a frame by wrapping the loopportions around the strut member and threading a cord through the loopportions.

FIG. 18 is a plan view of another embodiment of a leaflet skirt memberincluding loop portions formed with suture threads.

FIG. 19 is a cross-sectional view of a leaflet-skirt assembly includingthe leaflet skirt member of FIG. 18 secured to strut member of a frameand an outer skirt.

FIG. 20 is a process flow diagram illustrating a representative methodof securing a skirt member to a frame of a prosthetic valve.

DETAILED DESCRIPTION

The present disclosure concerns embodiments of implantable prostheticdevices and, in particular, implantable prosthetic valves, and methodsfor making such devices. In particular embodiments, the prostheticdevice comprises a prosthetic heart valve, and can be configured to beimplanted in any of the native heart valves. In addition, the prostheticheart valve can be, for example, a transcatheter heart valve, a surgicalheart valve, or a minimally-invasive heart valve. The prosthetic valvealso can comprise other types of valves implantable within other bodylumens outside of the heart or heart valves that are implantable withinthe heart at locations other than the native valves, such astrans-atrial or trans-ventricle septum valves. In one aspect, aprosthetic heart valve includes one or more leaflet-skirt assembliesthat allow the valve leaflets to be quickly and accurately secured tostrut members of the frame without the need to suture the leaflets tothe strut members, or with minimal suturing.

FIG. 1 illustrates a representative embodiment of a prosthetic heartvalve 100, according to one embodiment. The illustrated valve is adaptedto be implanted in the native aortic annulus although, in otherembodiments, it can be adapted to be implanted in other native annulusesof the heart. The valve 100 illustrated in FIG. 1 includes a stent, orframe, 102, and a valvular structure 104. Certain embodiments can alsoinclude an outer skirt (e.g., a perivalvular leakage skirt or sealingmember) secured to the outside of the frame, as shown in FIG. 11.

The valvular structure 104 can comprise three leaflets 106, collectivelyforming a leaflet structure, which can be arranged to collapse in atricuspid arrangement. The lower edge of leaflet structure 104 desirablyhas an undulating, curved scalloped shape. For instance, with referenceto FIGS. 1 and 6, each leaflet can include a main body portion 108including curved side portions 110 and a lower portion 112 such that theleaflets 106 have a scalloped shape. By forming the leaflets with thisscalloped geometry, stresses on the leaflets are reduced which, in turn,improves durability of the valve. Moreover, by virtue of the scallopedshape, folds and ripples at the belly of each leaflet (the centralregion of the main portions 108 of the leaflets), which can cause earlycalcification in those areas, can be eliminated or at least minimized.The scalloped geometry also reduces the amount of tissue material usedto form the leaflet structure, thereby allowing a smaller, more evencrimped profile at the inflow end of the valve. The leaflets 106 can beformed of pericardial tissue (e.g., bovine pericardial tissue),biocompatible synthetic materials, or various other suitable natural orsynthetic materials as known in the art and described, for example, inU.S. Pat. No. 6,730,118, which is incorporated by reference herein.

The frame 102 can be formed from a plurality of angled strut members114, and can have an inflow end 158 and an outflow end 160. The strutmembers 114 can be arranged to form a plurality of open cells 116arranged in rows. The cells 116 can be configured to receive commissurestructures 118 of the leaflet structure 104. For example, in theembodiment of FIG. 1, the uppermost row of cells 116 can be configuredto receive commissure tabs 120 of the leaflets 106. The commissure tabs120 can be secured (e.g., by suturing) to the strut members 114, therebysecuring the leaflets to the frame and allowing the leaflets to open andclose at the commissures in response to changes in blood pressure. Insome configurations, the frame 102 can be formed with a plurality ofspecially-shaped and circumferentially spaced slots, or commissurewindows (e.g., three commissure windows) that are adapted to mount thecommissures of the valvular structure to the frame, as described, forexample, in U.S. Patent Application No. 2012/0123529, which isincorporated herein by reference.

The frame 102 can be made of any of various suitableplastically-expandable materials (e.g., stainless steel, etc.) orself-expanding materials (e.g., Nitinol) as known in the art. Whenconstructed of a plastically-expandable material, the frame 102 (and,thus, the valve 100) can be crimped to a radially compressed state on adelivery catheter and then expanded inside a patient by an inflatableballoon or equivalent expansion mechanism. When constructed of aself-expandable material, the frame 102 (and, thus, the valve 100) canbe crimped to a radially compressed state and restrained in thecompressed state by insertion into a sheath or equivalent mechanism of adelivery catheter. Once inside the body, the valve can be advanced fromthe delivery sheath, which allows the valve to expand to its functionalsize.

Suitable plastically-expandable materials that can be used to form theframe 102 include, without limitation, stainless steel, a nickel basedalloy (e.g., a cobalt-chromium or a nickel-cobalt-chromium alloy),polymers, or combinations thereof. In particular embodiments, frame 102is made of a nickel-cobalt-chromium-molybdenum alloy, such as MP35N™(tradename of SPS Technologies), which is equivalent to UNS R30035(covered by ASTM F562-02). MP35N™/UNS R30035 comprises 35% nickel, 35%cobalt, 20% chromium, and 10% molybdenum, by weight. It has been foundthat the use of MP35N to form frame 102 provides superior structuralresults over stainless steel. In particular, when MP35N is used as theframe material, less material is needed to achieve the same or betterperformance in radial and crush force resistance, fatigue resistances,and corrosion resistance. Moreover, since less material is required, thecrimped profile of the frame can be reduced, thereby providing a lowerprofile valve assembly for percutaneous delivery to the treatmentlocation in the body.

Returning to the leaflet structure 104, the leaflet structure cancomprise a plurality of leaflet-skirt assemblies 122. With reference toFIGS. 1 and 6, each leaflet 106 can include a peripheral leaflet skirtmember 124 (also referred to as a connecting skirt) secured to theleaflet along the peripheral edges of the side portions 110 and thelower portion 112 of the main body 108 of the leaflets. The leafletskirt 124 can then be wrapped around and secured to the strut members114 of the frame to attach the leaflet to the frame.

FIGS. 2-5 illustrate various embodiments of leaflet skirts 124 ingreater detail. A representative leaflet skirt 124 is shown in FIG. 2,and can include a main body portion 130 having longitudinal edgeportions 132A and 132B. A plurality of extension portions of varyingsizes, such as first extension portions indicated at 126, can extendfrom the edge portions 132A, 132B of the main body 130, and can beseparated from one another by gaps or recessed portions 144. Theextension portions can include tubular portions 128 (e.g., located alongthe edges of the extension portions 126). The tubular portions 128 candefine respective lumens 138 (see FIGS. 8 and 9) which, when laid flat,can be substantially coaxial, as indicated by center lines 140 and 141.

The extension portions 126 can have width dimensions W extending in adirection parallel to the length of the leaflet skirt 124. The widthdimensions W of the extension portions 126 can vary according to, forexample, their location along the length of the skirt 124, the spacingbetween extension portions, the size and shape of the strut members ofthe frame, the size and shape of the cells 116 of the frame, and/or thesize and shape of the leaflets 106. For example, the embodiments ofFIGS. 2-4 can include first extension portions 126 having a first widthdimension W₁, second extension portions 148 having a second widthdimension W₂, and third extension portions 150 having a third widthdimension W₃. In the embodiments of FIGS. 2 and 3, the width dimensionW₃ of the third extension portions 150 is larger than the widthdimension W₂ of the second extension portions, and the width W₁ of thefirst extension portions 126 is greater than both the widths W₂ and W₃.However, it should be understood that the various extension portions canhave any suitable width dimensions. For example, FIG. 4 illustrates analternative embodiment wherein the width of the second extensionportions 148 is greater than the width of the third extension portions150. In another embodiment illustrated in FIG. 7, the width dimensionsof the first extension portions 126 and the width dimensions of thesecond extension portions 148 can be substantially equal.

Returning to FIG. 2, the first, second, and third extension portions126, 148, 150 can also have length dimensions L. In the embodimentsillustrated in FIGS. 2-4, all of the first, second, and third extensionportions 126, 148, 150 have the same length dimension L. However, itshould be understood that one or more of the first, second, and/or thirdextension portions can have different length dimensions L, as desired.In some embodiments, certain first, second, and/or third extensionportions can also have different length dimensions L from other first,second, and/or third extension portions.

In the illustrated embodiments, the first extension portions 126 can belocated at a central portion 142 of the leaflet skirt 124 such that whenthe skirt is attached to the leaflet 106, the first extension portions126 are adjacent the lower portion 112 of the leaflet (see, e.g., FIGS.1 and 6). In some embodiments, the width W₁ of the first extensionportions 126 can be, for example, greater than 50%, greater than 60%,greater than 70%, or greater than 80% of the length of the lower portion112 of the leaflet 106, as desired.

The second extension portions 148 can be arranged in an alternatingfashion such that extension portions 148 located on side portion 132Aare offset from extension portions 148 located on side portion 132B in adirection along a longitudinal axis 146 of the skirt, as illustrated inFIGS. 2-4. In some embodiments, the second extension portions 148 can beoffset from one another along the side portions 132A, 132B by a distanceless than, equal to, or greater than, the width dimension W₂, asdesired. For example, with reference to FIG. 2, the extension portion148B on side portion 132B can be offset from the extension portion 148Aon side portion 132A by a distance approximately equal to the widthdimension W₂ (measured from the center of one side portion to the centerof the other side portion). Meanwhile, the extension portion 148C can beoffset from the extension portion 148B by a distance greater than thewidth dimension W₂, such that there can be a gap or spacing between theadjacent edges of the side portions along the length of the skirt.

In some embodiments, the second extension portions 148 can be sized andspaced apart from one another along the length of the leaflet skirt suchthat one or more extension portions 148 are located within respectivecells 116 of the frame 102 when the leaflet-skirt assembly 122 issituated in the frame. For example, in the embodiment of FIG. 1, theextension portions 148 are sized and spaced apart such that twoextension portions 148 are located within each cell 116 along the sideportions 110 of the leaflets 106. Alternatively, any suitable number ofextension portions 148 can be located in the cells 116, such as threeextension portions (see FIGS. 8 and 10) or more, or a single extensionportion, as desired. This can facilitate accurate alignment of theleaflet-skirt assembly 122 within the frame 102 because the extensionportions are pre-configured to align with the desired position of theleaflet-skirt assembly in the frame.

Returning to FIGS. 2-4, the leaflet skirt 124 can include thirdextension portions 150 located at the end portions of the leaflet skirt.In the illustrated configurations, the width dimensions W₃ of the thirdextension portions 150 can be greater than the width dimensions W₂ ofthe second extension portions 148 but less than the width dimensions W₁of the first extension portions 126, although it should be understoodthat other configurations are possible. When the leaflet 106 and theskirt 124 are assembled together, the third extension portions 150 canbe located adjacent (e.g., below) the commissure tabs 120 of theleaflet, as shown in FIGS. 1 and 6.

Referring still to FIGS. 2-4, the lumens 138 of the tubular portions 128can have a diameter D. The diameter D of the lumens 138 of the tubularportions 128 can be varied according to, for example, the diameter ofcords, sutures, threads, etc., that are to be threaded through thetubular portions 128, as further described below. For example, FIG. 2illustrates an embodiment wherein a diameter D of the lumens 138 issubstantially equal to a length L of the extension portions 148. Incontrast, FIG. 3 illustrates an embodiment in which the diameter D ofthe lumens 138 is smaller than the length L of the extension portions126.

Referring to FIG. 5, the leaflet skirt 124 can be made from a ribbon orstrip 134 of material defining tubes or lumens 136 extending along sideportions of the strip 134. The tubes 136 can be cut (e.g., by lasercutting) to form the first, second, and third extension portions 126,148, 150 with the appropriate length, width, and spacing. The strip 134and, hence, the leaflet skirt 124, can be made from any of variousbiocompatible materials with suitable flexibility and/or sutureretention properties, including various woven fabrics such as gauze,polyethylene terephthalate (PET) fabric (e.g., Dacron®), polyesterfabric, polyamide fabric, or any of various non-woven fabrics, such asfelt. The skirt 124 can also be made from woven natural fibers such assilk, cotton, etc. Alternatively, the skirt 124 can also be made fromany of various polymeric material films, such as PTFE, PET,polypropylene, polyamide, polyetheretherketone (PEEK), ultra highmolecular weight polyethylene (UHMWPE) (e.g., Dyneema®), etc. The skirtcan also be made from various composite materials, such as UHMWPE filmreinforced with suture, such as Force Fiber® suture.

Turning now to assembly of the leaflet 106 and the leaflet skirt 124,the leaflet 106 can be positioned such that the lower portion 112 isadjacent the central portion 142 of the leaflet skirt 124, as shown inFIG. 6. The leaflet skirt 124 can then be folded about the peripheraledge of the lower portion 112 and the side portions 110 such thatperipheral edge is positioned generally along the longitudinal axis 146of the leaflet skirt. The extension portions 126, 148, 150 of thelongitudinal edge portion 132A of the skirt can be disposed on anoutward-facing surface 152 (e.g., the surface facing radially outwardwhen the leaflet is positioned in the frame 102), and the extensionportions 126, 148, 150 of the longitudinal edge portion 132B of theskirt can be disposed on an interior surface of the leaflet. The leafletskirt 124 can then be sutured to the leaflet generally along theperimeter of the scalloped main body 108 of the leaflet as indicated bysuture line 154 of FIGS. 1 and 6 to form the leaflet-skirt assembly 122.In some embodiments, a guide wire or cord or suture or thread 156 can bethreaded through the lumens 138 of the tubular portions 128. The guidewire 156 can aid in positioning the skirt 124 on the leaflet 106, andcan hold the skirt in place as it is sutured to the leaflet.

After the skirt 124 has been secured to the leaflet 106, theleaflet-skirt assembly 122 can be positioned inside the frame 102. Thefirst extension portions 126 can be folded upwardly around the lowerportion 112 of the leaflet 106. The second and third extension portions148, 150 can extend through the cells 116 of the frame, and can befolded around the strut members 114. More specifically, with referenceto FIGS. 8 and 9, adjacent sequential extension portions 148 along thelongitudinal axis of the skirt member can be wrapped around the strutmembers 114 in opposite directions such that the respective tubularportions 128 are coaxially aligned with one another on the outside ofthe frame. For example, referring to FIG. 8, when viewed from theoutflow end 160 of the frame, the extension portion 148A can be wrappedaround the strut member in a clockwise direction indicated by arrow 162.Extension portion 148B can be wrapped around the strut member 114 in acounterclockwise direction, as indicated by arrow 164, and extensionportion 148C can be wrapped around the strut member in the clockwisedirection, as indicated by arrow 174. This pattern of wrapping theextension portions 148, 150 around the strut members in oppositedirections can be repeated along the length of the side portions 110 ofthe leaflet 106. FIG. 9 illustrates a cross-sectional plan view throughthe strut member 114 of FIG. 8, and shows the leaflet skirt 124 foldedaround the edge of the leaflet 106, with the edge portions of the skirtthen folded back toward the strut member such that the extensionportions can be wrapped around the strut member.

When the extension portions 126, 148, 150 have been wrapped around thestrut members in the desired manner, a guide wire or cord member (e.g.,cord, suture, thread, etc.) 166 can be threaded through the tubularportions 128 of the extension portions 126, 148, 150 to secure theleaflet-skirt assembly 122 to the frame, as shown in FIGS. 1 and 10. Forexample, the cord member 166 can be threaded through the third extensionportion 150 on one side of the skirt 124, through the second extensionportions 148 and the first extension portion 126 on the outward-facingsurface 152 of the leaflet, and then through the second extensionportions and the third extension portion 150 on the opposite side of theskirt. In this manner, the cord member 166 can prevent the extensionportions 126, 148, 150 from unwrapping from around the strut members114. In some embodiments, the extension portion 126 on the inside of theframe can be held in place by the tension in cord 166. The extensionportion 126 on the inside of the frame can also be secured to otherfabric components of the valve, such as an inner skirt or an outer skirt(e.g., a PVL skirt) by, for example, sutures.

This process can be repeated for each leaflet-skirt assembly 122 to beplaced in the frame, so that the frame includes the appropriate numberof leaflets for the target heart valve (e.g., two leaflets arranged tocollapse in a bicuspid arrangement for the mitral valve, three leafletsfor the aortic valve, and three leaflets for the tricuspid valve). Inalternative embodiments, the cord member 166 need not be threadedthrough either of the first extension portions 126. Rather, at least thefirst extension portion 126 located on the outward-facing surface 152 ofthe leaflet can be pinned and retained against the outward-facingsurface of the leaflet by the strut members at the inflow end 158 of theframe.

After the cord members 166 have been threaded through the tubularportions 128, the end portions of the cord members 166, shown unsecuredin FIG. 1 for purposes of illustration, can be secured or otherwiselocated so as not to interfere with implantation or operation of theprosthetic device. For example, the end portions of the cord members 166can be tied to the strut members 114 of the frame, tied to one another,tied around or through the third extension portions 150, sutured to theleaflet skirt 124 other fabric components of the valve, and/or suturedto the leaflet 106, as desired.

Referring to FIG. 11, the cord members 166 can also be used to secure anouter skirt to the frame, such as perivalvular leakage (PVL) skirt 168.For example, in a representative embodiment, the PVL skirt 168 caninclude preformed slits or openings 170 that are located betweenextension portions 126, 148, 150 of the leaflet skirt 124 when the PVLskirt is placed around the frame. In the embodiment illustrated in FIG.11, the preformed openings 170 can be arranged in pairs, such as theexemplary pair of openings 170A, 170B. In this manner, as the cordmember 166 is threaded through the tubular portions 128 of the leafletskirt 124, the cord member can also be threaded through the firstpreformed opening 170A and back through the second preformed opening170B of the PVL skirt, before being threaded through the tubular portionof the next extension portion of the leaflet skirt. As shown in FIG. 11,the cord member 166 can form a “stitch line” 172 along the PVL skirt 168corresponding to the location of the side portion 110 of the respectiveleaflet 106. When two or more leaflet-skirt assemblies 122 are placed inthe frame, each of the respective cord members used to secure theleaflet-skirt assemblies to the frame can also be used to secure the PVLskirt 168 to the frame.

In another embodiment illustrated in FIG. 15, the openings 170 can beslits sized and located such that the tubular portions of the variousextension portions can be inserted through the respective slits in thePVL skirt. For example, FIG. 15 illustrates the tubular portions 128 ofthe extension portions 148 extending through the slits 170. The cordmember 166 can then be threaded through the tubular portions on theoutside of the PVL skirt to secure the PVL skirt to the frame.

The leaflet skirt and leaflet-skirt assembly embodiments describedherein can provide significant advantages over known prosthetic deviceassembly techniques. For example, the leaflet skirt 124 can providestrength and reinforcement to the edges of the leaflet that is typicallyprovided by a reinforcing strip, while at the same time providing a wayto quickly and accurately align the resulting leaflet-skirt assemblywith the frame 102. Because the various extension portions of theleaflet skirt 124 are configured to be aligned with specified cells ofthe frame, the leaflet-skirt assembly can be quickly and accuratelyplaced at the specified location within the frame. The leaflet-skirtassembly can also be quickly and reliably secured to the strut membersof the frame, without requiring any sutures. This can significantlysimplify the assembly process, reduce the cost and time required toassemble a valve, and increase yield by reducing positioning errorsduring the suturing process.

FIG. 12 is a process flow diagram illustrating a representative methodof making a leaflet-skirt assembly and placing the leaflet-skirtassembly in a frame of a prosthetic device. At block 202, a skirt membercan be secured to a valve leaflet to form a leaflet-skirt assembly. Theskirt member can include first and second longitudinal edge portions anda plurality of extension portions along at least one of the longitudinaledge portions. The extension portions can define tubular portions.

At block 204, the leaflet skirt assembly can be situated in a frame.

At block 206, the extension portions of the skirt member can be wrappedaround strut members of the frame to secure the leaflet-skirt assemblyto the frame.

FIGS. 13 and 14 illustrate alternative embodiments of the leaflet-skirtassembly. FIG. 13 illustrates a leaflet-skirt assembly 300 in which theleaflet skirt comprises two separate pieces of material 302, 304 securedon opposite sides of the leaflet 306 by suturing 310, or any othersuitable fixation method. The respective skirt members 302, 304 caninclude extension portions 308 located on respective longitudinal edgeportions of the skirt members similar to those described above withrespect to the embodiment of FIG. 1.

FIG. 14 illustrates another embodiment 400 in which the leaflet skirtcomprises a single piece of material 402 including a plurality ofextension portions 404. The skirt 402 is secured to one side of theleaflet 406 by suturing 408.

FIGS. 16 and 17 illustrate another method of securing various componentsof a prosthetic heart valve to a frame of the valve. FIG. 16 illustratesa representative example wherein a pair of threads, sutures, or chords502 are inserted through openings 504 defined in a skirt 506. Theopenings 504 are spaced apart from one another along an axiscorresponding to, for example, a longitudinal axis of a strut member(see FIG. 17) that will be adjacent the openings when the skirt issecured to a frame.

The skirt member 506 can define a primary surface 508 and a secondarysurface opposite the primary surface. The threads 502 can be threadedthrough the openings 504 such that they form curved extension portionsconfigured as loop portions 510 between successive openings on theprimary surface 508 of the skirt member. For example, with reference torepresentative loop portion 510A, the thread 502A can pass through theopening 504A to the primary surface side of the skirt member 506 andpass through the opening 504B to the secondary surface side of the skirtmember such that loop portion 510A originates at opening 504A andterminates at opening 504B. Alternatively, the loop portions canoriginate and terminate from the same opening, as desired.

As stated above, a pair of threads 502 can be inserted through theopenings 504 such that the loop portions 510 are formed in pairs. Asillustrated in FIG. 17, when the skirt member 506 is secured to a strutmember 512 of a frame, the skirt member can be positioned such that theprimary surface 508 is adjacent the strut member and the strut member islocated between the loop portions 510 of each respective pair of loops.A thread or cord member 514 can then be threaded through the loopportions 510 to secure the skirt member 506 to the frame. For example,as shown in FIG. 17, the cord member 514 can be threaded through theloop portions 510 in a crisscross pattern, with the cord passing througha loop portion on one side of the strut member 512, extending across alongitudinal axis 516 of the strut member, and passing through a loopportion on the opposite side of the strut member, etc.

When the cord member 514 has been threaded through a final selected loopportion (for example, the last loop portion on one side of the strutmember), the cord member can be threaded through the corresponding loopportion on the opposite side of the strut member 512, and the threadingprocess can be repeated along the strut member in the opposite directionsuch that the cord member overlaps or crosses itself along the length ofthe strut member between pairs of loop portions 510. In this manner, theloop portions 510 can be tied or laced to the strut member with the cordmember 514 in a manner analogous to shoe laces. This process can berepeated for each respective strut member 512 to which the skirt member506 is to be secured. In this manner, the skirt member 506 can besecured to the frame without forming individual stitches extendingaround the struts while the skirt is placed on the frame. Since the loopportions 510 are pre-formed prior to placing the skirt against theframe, substantial time can be saved in the manufacture of theprosthetic valve.

The above securing technique can be applicable to any suitable valvecomponent on which loop portions, such as the loop portions 510, can becreated. For example, the skirt member 506 can be an outer skirt, suchas a PVL skirt, or an inner skirt. The threads 502 and/or the cordmember 514 can be, for example, suture, or threads formed from any ofvarious natural or synthetic fibers, or polymeric materials.

The attachment technique illustrated in FIGS. 16 and 17 can also beapplicable to the leaflet-skirt assemblies described above with respectto FIGS. 1-15. For example, FIG. 18 illustrates an exemplary embodimentof a leaflet skirt member 600 including a plurality of extensionportions configured as loop portions 602 formed from threads 608. Theleaflet skirt 600 can have a first surface 604 and a second surfaceopposite the first surface, and can define a plurality of openings 606spaced apart from one another in a direction along a longitudinal axisof the leaflet skirt. Threads 608 can be threaded through the openings606 such that the threads form the loop portions 602 on the secondsurface.

Referring to FIG. 19, the leaflet skirt 600 can then be folded about andsecured (e.g., by suturing 610) to the edge of a leaflet 612 to form aleaflet-skirt assembly 620. The leaflet-skirt assembly 620 can besecured to a strut member 622 of a frame by a cord member 614 threadedthrough the loop portions 602 in a crisscross pattern, as describedabove. In the illustrated embodiment, this technique can also be used tosecure an outer skirt member 616 to the frame. For example, the loopportions 602 can be inserted through openings 618 defined in the skirtmember 616, and the cord member 614 can be threaded through the loopportions on a radially outward surface of the skirt member 616, as shownin FIG. 19.

FIG. 20 illustrates another representative method of securing a skirtmember to a frame of a prosthetic valve. At block 702, a skirt membercan be situated adjacent a strut member of a frame of a prostheticvalve. The skirt member can include a plurality of extension portions,such as the extension portions 148 formed from the material of the skirtmember 124, or extension portions configured as loop portions and formedwith suture threads.

At block 704, at least a portion of the plurality of extension portionscan be wrapped around the strut member.

At block 706, a cord member can be threaded through the extensionportions wrapped around the strut member to secure the skirt member tothe frame.

General Considerations

For purposes of this description, certain aspects, advantages, and novelfeatures of the embodiments of this disclosure are described herein. Thedisclosed methods, apparatus, and systems should not be construed asbeing limiting in any way. Instead, the present disclosure is directedtoward all novel and nonobvious features and aspects of the variousdisclosed embodiments, alone and in various combinations andsub-combinations with one another. The methods, apparatus, and systemsare not limited to any specific aspect or feature or combinationthereof, nor do the disclosed embodiments require that any one or morespecific advantages be present or problems be solved.

Although the operations of some of the disclosed embodiments aredescribed in a particular, sequential order for convenient presentation,it should be understood that this manner of description encompassesrearrangement, unless a particular ordering is required by specificlanguage set forth below. For example, operations described sequentiallymay in some cases be rearranged or performed concurrently. Moreover, forthe sake of simplicity, the attached figures may not show the variousways in which the disclosed methods can be used in conjunction withother methods. Additionally, the description sometimes uses terms like“provide” or “achieve” to describe the disclosed methods. These termsare high-level abstractions of the actual operations that are performed.The actual operations that correspond to these terms may vary dependingon the particular implementation and are readily discernible by one ofordinary skill in the art.

As used in this application and in the claims, the singular forms “a,”“an,” and “the” include the plural forms unless the context clearlydictates otherwise. Additionally, the term “includes” means “comprises.”Further, the terms “coupled” and “associated” generally meanelectrically, electromagnetically, and/or physically (e.g., mechanicallyor chemically) coupled or linked and does not exclude the presence ofintermediate elements between the coupled or associated items absentspecific contrary language.

In the context of the present application, the terms “lower” and “upper”are used interchangeably with the terms “inflow” and “outflow”,respectively. Thus, for example, the lower end of the valve is itsinflow end and the upper end of the valve is its outflow end.

As used herein, the term “proximal” refers to a position, direction, orportion of a device that is closer to the user and further away from theimplantation site. As used herein, the term “distal” refers to aposition, direction, or portion of a device that is further away fromthe user and closer to the implantation site. Thus, for example,proximal motion of a device is motion of the device toward the user,while distal motion of the device is motion of the device away from theuser. The terms “longitudinal” and “axial” refer to an axis extending inthe proximal and distal directions, unless otherwise expressly defined.

In view of the many possible embodiments to which the principles of thedisclosed technology may be applied, it should be recognized that theillustrated embodiments are only preferred examples and should not betaken as limiting the scope of the disclosure. Rather, the scope of thedisclosure is at least as broad as the following claims.

The invention claimed is:
 1. An implantable prosthetic valve that isradially collapsible to a collapsed configuration and radiallyexpandable to an expanded configuration, the prosthetic valvecomprising: an annular frame including a plurality of angled strutmembers; a plurality of leaflets disposed within the frame and securedto the frame; a skirt member secured to the frame, the skirt memberhaving a longitudinal axis aligned with an edge portion of a leaflet,the skirt member including a plurality of extension portions wrappedaround at least one strut member adjacent the extension portions; and acord member threaded through at least a portion of the plurality ofextension portions in a direction along the longitudinal axis of theskirt member to secure the skirt member to the at least one strutmember.
 2. The prosthetic valve of claim 1, wherein the skirt member issecured to the edge portion of the leaflet.
 3. The prosthetic valve ofclaim 2, wherein the skirt member comprises first and secondlongitudinal edge portions, and the plurality of extension portions arelocated on at least one of the longitudinal edge portions.
 4. Theprosthetic valve of claim 3, wherein the skirt member is folded aboutthe edge portion of the leaflet such that the first and secondlongitudinal edge portions extend from opposite sides of the leaflet. 5.The prosthetic heart valve of claim 2, wherein sequential extensionportions along the longitudinal axis of the skirt member are wrappedaround the at least one strut member in opposite directions.
 6. Theprosthetic heart valve of claim 5, wherein: the extension portionsdefine respective openings; and the extension portions are wrappedaround the at least one strut member such that the at least one strutmember is outside the bounds of the openings.
 7. The prosthetic valve ofclaim 6, wherein the extension portions define tubular portionscoaxially aligned with each other on the outside of the frame.
 8. Theprosthetic valve of claim 2, wherein the skirt member is secured to thevalve leaflet by suturing.
 9. The prosthetic valve of claim 2, furthercomprising two leaflets and associated skirts members configured tocollapse in a bicuspid arrangement, or three leaflets and associatedskirt members configured to collapse in a tricuspid arrangement.
 10. Theprosthetic valve of claim 1, further comprising an outer skirt securedto the frame with the cord member.
 11. The prosthetic valve of claim 10,wherein at least a portion of the plurality of extension portions areinserted through openings defined in the outer skirt, and the cordmember is threaded through the extension portions extending through theopenings to secure the outer skirt to the frame.
 12. The prostheticvalve of claim 1, wherein the extension portions are loop portionsformed from one or more sutures inserted through openings defined in theskirt member.
 13. The prosthetic valve of claim 12, wherein the loopportions are spaced apart from one another in a direction along alongitudinal axis of the at least one strut member.
 14. The prostheticvalve of claim 12, wherein the loop portions are arranged in pairs, andthe at least one strut member is located between the respective loopportions of at least one pair of loop portions.
 15. A method,comprising: situating a skirt member adjacent a strut member of anannular frame of a prosthetic valve, the skirt member including aplurality of extension portions and a longitudinal axis aligned with anedge portion of a leaflet; wrapping at least a portion of the pluralityof extension portions around the strut member; threading a cord memberthrough the extension portions wrapped around the strut member in adirection along the longitudinal axis of the skirt member to secure theskirt member to the frame; and repeating the situating, the wrapping,and the threading such that the prosthetic valve includes a plurality ofleaflets disposed within the frame and secured to the frame.
 16. Themethod of claim 15, wherein the wrapping further comprises wrappingsequential extension portions around the strut member in oppositedirections such that respective openings defined by the extensionportions are coaxially aligned with one another on the outside of theframe.
 17. The method of claim 15, further comprising securing the skirtmember to the edge portion of the leaflet by suturing.
 18. Animplantable prosthetic valve that is radially collapsible to a collapsedconfiguration and radially expandable to an expanded configuration, theprosthetic valve comprising: an annular frame including a plurality ofangled strut members; a plurality of leaflets disposed within the frameand secured to the frame; a skirt member secured to an edge portion of aleaflet of the plurality of leaflets such that a longitudinal axis ofthe skirt member is aligned with the edge portion of the leaflet, theskirt member having first and second longitudinal edge portions and aplurality of extension portions on at least one of the longitudinal edgeportions, the extension portions defining tubular portions, at least aportion of the extension portions of the skirt member being wrappedaround at least one strut member; and a cord member threaded through atleast a portion of the tubular portions in a direction along thelongitudinal axis of the skirt member to secure the leaflet and theskirt member to the frame.
 19. The prosthetic heart valve of claim 18,wherein the extension portions of the skirt member are wrapped aroundthe at least one strut member in opposite directions such that thetubular portions are coaxially aligned with each other on the outside ofthe frame.
 20. The method of claim 19, further comprising securing anouter skirt to the frame with the cord member.